You don't need another "more DPS" lecture to stop getting deleted in Path of Exile 2. What you need is sustain that keeps working when the arena turns into a blender. That's why I keep coming back to Soul Tether, even when people call it vendor trash. It bends how life leech behaves: instead of wasting recovery once your life globe is full, the overflow pushes into Energy Shield and turns it into a second bar that's fed by damage. If you're already farming PoE 2 Currency and piecing together a real endgame kit, this belt is one of those sleeper items worth understanding.
Normally, leech has manners. It tops you off, then it stops. Soul Tether doesn't. Keep hitting, keep leeching, and the extra recovery keeps rolling into ES. It feels like you're "healing" a shield that usually only comes back after you've been out of trouble for a bit. In practice, it smooths out chip damage and makes small mistakes way less punishing. You'll notice it most in dense maps or messy rares where you're always taking little hits, because that overflow leech keeps your buffer from collapsing.
People bring up Essentia Sanguis because it points in the same direction, but it's not the same deal. Gloves are prime real estate. Most builds need them for attack speed, res fixes, conversion, or some build-defining mod. And Essentia's trade-off is harsh: it converts your leech away from life, so you don't get that "both bars move" feeling. Soul Tether's big win is that you can leech life and also keep topping ES through overflow. It's a layered defence, not a swap.
Yes, the belt comes with a nasty line: a constant drain of 5% of your maximum Energy Shield per second. On paper it looks like self-sabotage, and in long boss phases it often is. If you've ever watched your ES melt while you're forced to dodge and can't hit anything, you get why folks ditch it. The belt asks you to stay aggressive, and the game doesn't always let you.
Here's where it flips. If you corrupt Soul Tether and then use a Vaal Cultivation Orb, there's a chance that drain mod gets removed entirely, replaced by something you actually want. Rolls like faster leech rate (up to 25%) change the feel immediately, and the mod that applies your base life regen to Energy Shield is huge for characters that hate downtime. CI players especially benefit, because it gives ES builds a more "active" sustain plan instead of waiting around. If you're shopping for a good base or trying to price one fairly, it helps to keep an eye on the poe2 market before you sink more orbs into the gamble.